1. Field of the Invention
The invention proposes a stator for an electric rotary machine comprising a coil formed from a plurality of lead wires, which are distributed in the slots of the core in an optimized manner.
The invention proposes more particularly a stator for an electric rotary machine which comprises an annular core, with its principal axis being vertical overall, which is delimited axially by an upper face and by a lower face, and which is delimited radially by an annular internal face, a set of axial slots provided in the annular internal face of the core and which open out in the upper face and in the lower face of the core, and a coil comprising a plurality of windings of the type in which each winding consists of at least one conductor which is arranged in slots of the core associated with the winding, forming axial ripples and forming overall a spiral coaxial to axis A of the core which consists of a set of turns radially superimposed.
2. Description of the Related Art
According to an embodiment of the prior art, each coil comprises one or several conductors in a spiral, each turn of which forms ripples covering the slots of the core.
To improve the performance of the electric machine, it is preferable to fill the slots of the core to the maximum, while optimizing the flow sections of the magnetic flux.
For this reason, with regard to stators used in alternators intended in particular for automotive applications, it has been proposed to build up the stator so as to allow two strands of conductors to be assembled in each slot at the same radial dimension relative to the principal axis of the stator.
A solution of this kind allows the load factor of each slot to be increased and also increases the number of strands of each coil.
This increase in the number of strands of the windings poses certain problems as regards the coil snarls, as the arrangement of the strands of each lead wire, forming the snarls, is not optimized. The result is that the radial thickness of each snarl of a coil formed from lead wires with reduced cross-section, according to such a solution, is greater than the thickness of a snarl of a coil comprising a reduced number of lead wires with larger cross-section.